The SS Ephialtes was an Antaeus-class civilian superfreighter operating in the 23rd century. It had a top speed of warp six and functioned primarily as a colony support vessel. It was commanded by Captain Alodae and had 25 crew and officers.
In 2268, the Ephialtes and her crew were commandeered by Starfleet at Starbase 47-Vanguard. Under the orders of Admiral Heihachiro Nogura, and with legal support from Holly Moyer of the Judge Advocate General's office, the freighter's cargo bay was gutted so it could smuggle the Archer-class scout, USS Sagittarius, away from the station without being detected by the Klingons or Romulans. Sensor blocking equipment installed aboard made it seem like the cargo was unrefined minerals.
However, at the Iremal Cluster, the freighter was intercepted by the IKS vaQjoH and ordered to surrender and prepare to be boarded. The Klingons were thwarted from their attempt at plunder by the USS Enterprise which, acting on intelligence from Vanguard, had been lying in wait in a planetary debris field nearby. (VAN novel: Storming Heaven)